SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5c0dbfdf89eebf2580048849b2dabfe70c106fea1cdb05763a3c535dbecaac18' 
  AND token = 'XJk+5x8DIreQjvdsonpxv7Ncbh5jTvcmH05EOWEoKz0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}